Pulverized-fuel burner



Dec. 15 1925- 1,566,177

, w. H. WHITAKER 1 I I PULVERIZED FUEL BURNER Original Filed June 25 1923 Qwvwwtoz @wmw Patented Dec. 15, 1925.

UNITED sTATEs PATENT OFFICE.

WILLIAM H. WHITAKER, F SHELBYYILLE, ILLINOIS.

IULVERIZED-FUEL BURNER.

Application filed June 25', 1923, Serial No. 647,681. Renewed June 1, 1925. i

To all whom it may concern: y

Be it known that I, WILLIAM H. WHIT- AKER, a citizen of the United States, and a residentof Shelbyville, in the county of Shelby and State of Illinois, have invented a new and useful Improvement in a Pulverized-Fuel Burner, of which the following is a specification.

My invention relates to pulverized fuel burners and its all important object is to provide such a burner as will spray the combustible mixture over the fire box of a furnace or the like in the form of a sheet.

A further object of the invention is to provide a burner of this character which will spray the pulverized fuel over the entire surface of the fire box and which during the passage of the pulverized fuel through the burner will draw in a quantity ofair for mixing with the powdered fuel and thereby produce a highly combustible mixture.

Another object is to provide a burner upon which the powdered fuel will not slag, so that there is no necessity of repeatedly throwing the furnace out of operation to clean the burner.

With the preceding and other objects and advantages in mind, the invention consists in the novel combination of elements,

constructions and arrangement of parts and operations to be hereinafter enlarged upon, claimed and" illustrated in the accompanying drawings, wherein:

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nated generally by the numeral 10, one end "of this block 10 being supported in the opening 6 as shownin Fig. Formed in the block or member 10 is a; relatively large horizontally disposed opening 11 which extends from end to end Figure 1 is a front elevation of a furnace her or block formed of fire brick and desig-' frusto-pyramidal of this member 10 and has its smallest end located at the inner end of the member 10.

Secured to the outer face of the-block or member 10 is a rectangular angle-iron frame 12 and secured to this frame 12 and spaced from the horizontal members thereof is a smaller rectangular frame '13. Extending horizontally of the frame 13 and having its ends secured to the end members of this frame is an elongated plate 14 whose longitudinal edges are spaced from the horizontal members of the frame 13. This manner of spacing the plate 14 and frames 12 and 13 affords air ports 15. For these air ports 15 damper plates 16 are pivoted 'to the frames 12 and 13. These damper plates are adapted to be normally disposed in the open position illustrated in Fig. 3.

The plate 14 is provided with an intermediate circular portion 17 having a circular pulverized fuel inlet 18. A collar 19 is secured to the outer face of this plate 17 for connection with a pulverized fuel conducting pipe 20 adapted to conduct pulverized fuel and air under pressure from any suitable source, not shown. Extending rearwardly from the rear face of the plate 14 is a discharge nozzle 21. This nozzle 21 is substantially rectangular in cross section and the bottom and top thereof converge toward the inner end thereof while the side walls thereof diverge, as shown in Fig. 4, thus providing an elongated rectangular mouth or discharge outlet 22.

Caried by the inner face of the frame 13 and housing the nozzle 21 is a second nozzle 22 which is substantially rectangular in cross section and whose walls converge toward the inner end thereof and provide a relatively large rectangular opening 23 which is co-axial with the discharge opening 22 of the nozzle 21.

Inthe operation of the burner the pulverized fuel and air are discharged into the nozzle .21 from the pipe 20. As this fuel enters'the nozzle 22 a suction is created in the rear end of this nozzle drawing air through the ports 15 between the frame 13 and bar 14. The pulverized fuel continuing through the discharge opening 23 in the nozzle 22 draws in a further quantity of air through the air ports 15 between the frame 13 and the frame 12. It will be thusapparent that my improved burner not only provides a combustible mixture having a maximum sup-ply of oxygen but injects the combustible mixture over the tire box of the furnace in the form of a sheet.

In certain forms of powdered fuel burners heretofore devised, an air supply passage member surrounds the fuel supply nozzle, but the inner ends of the nozzle and passage member are not protected against the heat from the fire box and consequently the fuel slags thereon and it is frequently necessary to throw the furnace out of operation to clean the burner. In my invention however, the passage member or pipe 22 which surrounds the fuel nozzle 22, projects inwardly beyond said nozzle to protect the same from excessive heat, by supplying the incoming cool air from the pipe 22 around the tip of the nozzle. To in turn protect the air inlet pipe 22' against heat from the fire box, suflicient to slag the fuel thereon, the air passage member 10 projects inwardly beyond said pipe, so as to supply more cool air around the end of the pipe. Also, the two quantities of incoming cool air, passing through the member 10 and the pipe 22 maintain the inner end of said member 10 at a sufficiently low temperature to prevent slagging? of the fuel thereon, even though the fuel be admitted at a low velocity and burns rather close to said member. Attention is also directed to the fact that the top, bottom and vertical side walls of the pipe '22 and the passage 11, converge to the inner extremities of said pipe and passage, so that their inner faces do not face the flame within the fire-box. They are thus further shielded against being extensively heated, and having a tendency to melt or slag any fuel which might contact with them. I also wish to direct attention to the independent dampers for controlling the entrance of air into the upper and lower portions of the pipe 22 and the passage 11., By properly controlling these dampers, the direction taken by the flame as the latter is projected from the burner, may be accurately controlled.

In order to cool the grate (not shown) of' the furnace 5 openings controlled by dampers 25 are provided in the front wall of the, furnace. This also prevents slag from forming in the furnace.

It is to be understood that the form of my invention herein shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

I claim 1 1. A pulverized fuel burner comprising a fuel su ply nozzle horizontally widened at its disc arge end and adapted at its outer end for connection with a supply pipe for pulverized fuel and fluid under pressure an air inlet pipe surrounding said nozzle 1n spaced relation therewith and projecting 1n wardly beyond said nozzle, said pipe being of greater width than height, the top, bot: tom and side walls of said pipe converging to the inner extremity of the latter and the outer end of said pipe being open to free air to admit the same, and an air inlet passage member surrounding said pipe in spaced relation therewith and projecting inwardly beyond said pipe, said passage member being of greater width than height, the top, bottom and side walls of said passage member converging to the inner extremity of the latter and the outer end of said passage member being open to free air to admit the same.

2. A pulverized fuel burner comprising a nozzle adapted for connection to a supply pipe for powdered fuel and air under pressure, an air inlet pipe surrounding said nozzle in spaced relation therewith and projecting inwardly beyond said nozzle, the outer end of said pipe being open to free air to admit the same, an air inlet passage member surrounding and extending inwardly beyond said pipe, the'outer end of said passage member bein open to free air, independent upper an lower dampers for controlling the entrance of air into the upper and lower portions of said pipe, and additional independent dampers for controlling the entrance of air into the u per and lower portions of said passage mem er.

3. A pulverized fuel burner comprising a stationary internally unobstructed fuel nozzle having transversely straight relatively wide top and bottom walls which converge to the inner end of said nozzle and having relatively narrow vertical side walls which diverge to said inner end, providing a horizontally widened outlet for pulverized fuel and fluid under pressure, a stationarily secured internally unobstructed air inlet pipe around and spaced from all sides of said nozzle, said pipe extending beyond the inner end of said nozzle and having relatively wide transversely straight top and bottom walls and comparatively narrow transversely straight vertical side walls all converging to the inner extremity of the pipe. the outerend of said pipe being open to free air to admit the same, a stationarily secured internally unobstructed passage member around and spaced from all sides of said pipe, said passage member extending beyond the inner end of the pipe and having relatively wide transversely straight top and bottom walls and relatively narrow transversely straight vertical side Walls all converging inwardly to the inner extremity of said member, the outer end of said passage member being open to free air to admit the same, independent dampers for controlling the entrance of air into the up or and lower portions of said pipe, and in ependent dampers for controlling the admission of air into the upper and lower portions of said passage member.

4-, A pulverized fuel burner comrising an open'rectangular frame adapte to be mounted verticallyon the outer. end of a' passage member, a smaller open rectangular frame having upper and lower side members spaced inwardly from the corresponding members of the larger frame andhaving its vertical side members secured to the vertical side members of said larger frame, a vertical plate spanning said smaller frame hori= zontally and secured at its ends to said vertical side members thereof, the upper and lower edges of said plate being spaced in- Wardly from the upper and lower side members of said smaller frame, said plate having 26 a central inlet for pulverized fuel and fluid under pressure, a nozzle secured to said plate passage member and said air i e. 

